Born in Bari, he began his football career with hometown club A.S. Bari, entering the youth system. He made his debut at the end of the 2008–09 Serie B season, on 16 May 2009, replacing Daniele De Vezze in a 4–1 win against Modena. He was confirmed for the first team the following season, but never played, instead he continued to play with the youth team. In July 2010, he was loaned to Lucchese along with Alessandro Marotta, but in August moved to Barletta. He played the league first match as substitute, replaced defender Alessio Lanotte and started as the attacking midfielder in the next round. He was the playmaker in 4-3-1-2 formation or one of the supporting striker in 4-3-2-1 formation. On 1 July 2011 he signed a new 3-year contract with Bari.
On 27 August 2012, half of the registration rights of Bellomo was sold to Cheivo for €1.75 million. Bellomo immediately returned to Bari in temporary deal.
On 3 July 2013 Bellomo was sold to Serie A club Torino for €1.2 million with Chievo retaining 50% of his registration rights in co-ownership. He made his debut for the Granata during the third round of the 2013–14 Coppa Italia against Pescara, lost 1–2, and in Serie A on 25 September playing a full match against Hellas Verona, 2–2. On 20 October he scored his first goal in Serie A from a free kick to draw Torino level against Inter Milan in the 90th minute and the match ended 3–3. In a post-match interview Bellomo dedicated the goal to his late father. Bellomo made 7 appearances for Torino during the 2013–14 season before he was loaned to Spezia in Serie B on 29 January 2014.
Spezia (loan)
At Spezia, he was given the number 10 shirt, making his debut 1 February 2014 in a draw 1–1 against Juve Stabia. After contributing two assists on 15 Februaryat home against Crotone, he scored his first goal for the Aquilotti on 22 March against Brescia. He scored again on 12 April away to Cesena, before deciding the following match against Siena, 1–0. He was decisive again on 3 May, scoring the 2–1 against Regina, bringing Spezia into the play-off zone of the league table. With Spezia, he played in the quarter-finals of the promotional play-offs, losing 1–0 to Modena. He concluded the season with 21 appearances and 5 goals.
Return to Chievo
On 21 June 2014 the co-ownership between Chievo and Torino was resolved in favour of the former for a fee of €343,000.
Bellomo began as a central midfielder, but in recent seasons at Bari was often employed in a playmaking role. He is right footed, with a good shot from distance and competent at set pieces. Said to be inspired by Marco Verratti.
